Thermostat and reversing-valve.



No. 7 1,4 2. I PATENTED MAY'31, 1904."

'F. w. ROBERTSHAW.

THERMOSTAT AND REVERSING VALVE.

APPLIOATIQN FILED JAIL 13.1903

" NOIMODEL- 2 SHEETS-SHEET 2.

UNITED, STATES- Patented May 31, 904.

PATENT OFFICE.

,THEBMOSTAT AND REV ERSING-VALVE.

SPECIFICATION forming part of Iletters Patent No, 761,402, dated May 31 1904.

Application filed 'anuary 13,1903. Serial No. 138,864." (No man.)

T aZZ whom it may concern 'Be it known that I, FREDERICK W. ROBERT- SHAW, a resident of Pittsburg, in the, county of Allegheny and State of Pennsylvania, have invented a new and useful Improvementin Thermostats and Reversing-Valves; and I do hereby declare the following to be a full, clear, and exact description thereof. V

My invention relatesto water-heaters, and

. more especially to automatic waterheaters wherein the water is heated by gas, the flow of which is automatically increased whenever a faucetis opened in any part of the system and-is automatically decreased when faucets are closed.

One of the objects of my invention is to provide a simple and eflicient combined thermostat and gas-valve for controlling the flow of gas to the burners of the'heater according, to the temperature of the water in the system and which will bring on the gas as soon as a little hot water is drawn. r

A further object'of my invention is to pro vide a reversing-valve, thermostat, and gasvalve all combined in a single fitting, so that 1 these parts can be accurately put together and adjusted in the factory, and said fitting can then be attached to the system without change by an ordinary plumber, thus dispensing with one of'the sources'of annoyance in apparatus of this'kind resulting from a lackof skill on the part ofthe plumber in properly adjusting thevalves and thermostat;

In the accompanyingd rawings, Figure 1 is a side elevation, partly in section, of a water system showing my improvement, applied thereto; and Fig. 2 is a vertical section through the reversing valve, thermostat, and gas valve.-

My invention may be employed in connec tion with waterheating systems of anykind, such as the ordinary domestic systems found inhouses, or even for hot-waterheating systerns. I have shown the invention used in connection with an ordinary water reservoir or boiler 1, supported upona suitable stand or bracket 2 and having its top end connected by all of the ed to'the water-supply and lower end of the 'form. This pipelis shown inclosed in a casing 6, in the lower end of which is the gasburner 8, supplied through the pipe 9. This form of heater has been selected for purposes of illustration merely, and the invention is not limited thereto, as in place thereof any @i'orm of heater may be employed, such as the range or a heater-pipe of any known form and heated in any known manner, it only be mg necessary that whatever form of heater .fluid fuel, such as gas or oil, be employed.-

The lower end of the heater-pipe is connectboiler or reservoir, and in'this connection I place a suitable reversing-valve, that shown in the drawings being a valv'e'described and claimed in my' patent, reissued October 21, 1902, No! 12,046. This valve comprises a suitable casing 10, having a cylindrical chamber 11, in which the valve mechanism works. ,Thecasing-has a feed-port 12, to which at its lower end the cold-water pipe is connected, l and two circulation-ports at different heights,

pipe 5 by means of a pipe 1 1, while the other port, 15, is connected to the lower end of the boiler by means of a pipe 16 projecting into the lower head of said boiler, so that the cold ,water is discharged near the bottom of the boiler. The hot-water or service pipe 17 will be connected at anysuitable place so as to draw the. water from the lower end of the heater-pipe without causing it to pass through the reversing-valve, this connection preferably being made to the pipe 1 1 between the valve and the heater-pipe 5Q V l p In the valve-chamber 11 works a double-pis ton valve 18, comprisinga lower motor-piston 19 andupper piston or valve 20, which pref erably are of different diameters, so as to form a differential valve. The piston-valve has a guide-stem 21 projecting upwardly into'a'n opening 22 in the cap of the casing, and the piston is provided with guiding arms or projections 24. l A spiral spring 25 surrounds I the stem 21- and acts normally to hold the pispipe is employed some form of burner using one of which, 13, is the main circulation-port and is connected to the lower end of the heaterthe boiler through or into close proximity to" ordinary coil located in the water-back of a able thereon-such, for instance, as by screwing the same on the stem, as shown. In order to ad3ust the valve on the stem, the former is provided with oppositeprojections or wings screw-threaded connections, as shown.

34, whereby the disk can be turned. A lock-nut 35 holds the disk in its adjusted position. The lower end of the valve-casing is provided with the screw-cap 37, by means of which access can be had to the interior thereof in order to adjust the disk 32 at the factory. The disk 32 is made thin at its center, preferably by having annular corrugations 36 formed therein, so that it will yield or spring, so as to relieve the threaded connection with the rod 33 of excessive strain as might otherwise occur if the fitting 39 overheated or if there is any obstruction to the closing of the valve.

The valve 28 is provided with a yoke 38, whereby it is secured to a fitting 39, which is in the form of a pipe-section placed in vertical position. Any connecting means may be used for securing the yoke 38 to the pipe-section 39; but preferably they are formed with The pipe-section 39 communicates at its lower end with the circulation-port 15 of the reversingvalve and at its upper end with the pipe 16, leading to the lower end of the boiler. The valve-stem 33 extends upwardly into the pipesection 39 and is secured to a plug 40, threaded through the upper end of the pipe-section 39. The plug 40 is provided with a squared end 41 or the like for receiving a wrench for turning the same in order to adjust the valve 32 without interrupting the flow of gas. A cap 42 protects the upper end of the plug 40.

The rod 33 and pipe-section 39 are formed of metals having different coefficients of expansion under the influence of heat, and preferably the pipe-section is formed of brass, copper composition, or other metal having a high coefiicient of expansion, while the rod 33 is formed of high-grade steel or the like having a low coefficient of expansion. I prefer highgrade steel to iron, as it expands uniformly at all temperatures, whereas iron expands very little at low temperatures and relatively very much at high temperatures. The steel rod, therefore, insures an equal amount of valve-opening for relative variations of temperature. Suitable stufiing-boxes 43 and 44 are provided around the rod 33 where the same enters the pipe-section 39 and the gas-valve 28. The heater will preferably be placed as shown in the drawings-that is, mostly below the bottom of the boiler-in order that the circulation will not be retarded, as would occur if the heater were placed at a higher level. By extending the thermostat elements downwardly below the boiler, as shown, and said elements being acted on by the water said. elements will be kept cool as long as there is any cold water in the boiler, thus insuring the flow of gas to the burner until all the water in the boiler is heated. By making the thermostat, gas-valve, and reversing-valve as a single fitting and extending the thermostat below the boiler with the attaching connections, as shown, it is impossible for the plumber to place the heater so high that it will retard the circulation.

The operation of my reversing-valve and thermostat devices is as follows: When the faucets in the hot-water service-pipe are closed, the reversing-valve will be held by the spring 25 in the position shown in Fig. 2, with the motor-piston 19 closing the feed-port 12 and the circulation-ports 13 and 15 open. In this position the cold water from the bottom of the reservoir 1 will pass into the pipe 16, through the pipe-section 39, and through the port 15 into the valve-chamber 11 and from thence through the port 13 and pipe 14 into the heating-pipe 5, from which the hot water passes through the pipe 4 into the upper end of the reservoir. As long as there is cold water in the boiler this circulation will eontinue and the cold water will pass through the thermostatic pipe-section 39, thus chilling both the pipe-section 39 and rod 33. This will cause a relative shortening of the pipe-section 39 as compared with the rod 33 and keep the disk valve 32 off the seat 31 and permit gas to flow to the burner 8. When all of the water in the boiler has been heated, hot water will begin to flow through the pipe-section 39 and reversingvalve to the heater. This will heat both the pipe-section 39 and rod 33, cansing them to expand; but by reason of thedifferent coefiicients of expansion of these parts the pipe-section 39 will expand more than the rod 33, thus causing the disk valve 32 to be brought into contact or close proximity with the seat in the gas-valve, either entirely cutting off or at least diminishing the flow of the gas to the burner. By means of this thermostatic device, therefore, the quantity of gas flowing to the burner will be regulated according to the temperature of the water flowing through the pipe-section 39, so that overheating of the water cannot occur. As soon as the faucet in the hot-water servicepipe is opened the pressure above the motorpiston 19 will be reduced, thereby permitting the pressure in the cold-water pipe 12 to raise the valve against the tension of the spring 25. In this movement the piston 19 opens the feedport 12, while the piston-valve 20 closes the passage through the valve-casing, thus cutting off the flow of water from the circulation-port tothe circulation-port 13, and the closing of this passage takes place,- as described in my patent aforesaid, before the piston 19 opens the feed-port12. In this position of the valve the cold water passes through the valve-casing, through the circulation-port 15, pipe-section 39, and pipe 16 into the lower end of the boiler. This will drive the hot water upwardly in the boiler, and said, hot water will pass through the pipe 4, down through the heating-pipe 5, and thence to the hot-water service-pipe, thus being reheated and passing through the heater-pipe in a direction opposite to its original course, thus cleaning out any sedimentthat may have been deposited therein. The cold water fromjthe' feed-pipe begins to pass through the pipesection 39 almost as soon as the hot-water faucet is opened, and it chills said pipe-section and the rod 33 and these parts will contract; but by reason of their different coefiicients of expansion the pipe-section 39 will contract more than the rod 33, thus, in effect, drawing the valve-seat away from the disk valve 32 and permitting more gas to flow to the burner 8, so that a high degree of heat is given the water flowing out of the servicepipe. As soon as the hotrwater faucet is again closed the reversing-valve 19 returns to the position shown in Fig. 2, thus again reversing the flow of water through the system and establishing the circulation first above described. The gas will continue to.

flow in undiminished quantity to the burner 8 until the temperature of the water flowing through the pipe-section 39 increases so as to cause the variable expansion of the thermostatic elements, as above described, and this will not occur until all the water in'the boiler has been heated.

It will thus be observed that by means of my improvements the circulation of the water through the boiler and heater is periodically reversed, and the quantity of gas flowing'to the burners is automatically regulated according to the temperature of the water in the system. The reversing-valve, thermo' static elements, and gas-valve are arranged in juxtaposition and directly connected to each other, so that they can be assembled and properly adjusted at the factory. In applying them to the system the plumber need only connect the pipe 14 and cold-water pipe to the reversing-valve, the pipe 16 to the fitting 39, and the gas-pipes to the inlet and outlet of the gasvalve. It will not be necessary for him to disturb any part of the combined reversing and gas valves and thermostatic elements, so that a lack of skillon the part of the plumber will not get these parts out of adjustment and he cannot place the heater at the wrong elevation. The gas-valve and pipe-section 39 preferably will be formed asa single casting; but for convenience in making and fitting these parts they maybe made in several'parts', as shown. 1 The reversing-valve will alw'aysbe separate and attached to the thermostat. In place of they gas-valve shown I may substitute an oil-valve ora valve for any other'form offiuid fuel.

What I claim as my invention, and desire to secure by Letters-Patent, is

1. In a water-heater, the combination with a reservoir, of a heater and heater-pipe, a connection between said reservoir and heaterpipe, a reversing-valve constructed and adapted to automatically'close the connection leading therefrom to the heater-pipe upon the withdrawal of water from the system, a feedpipe connected thereto, connections between said reversing-valve and theheater-pipeand between said reversing-valve and the reservoir, a thermostatic device located in said last-namedconnection, and'a fuel-supply valve for the heater controlled by said thermostatic device. 1

a reservoir, of a'heater and'heater-pipe, a connection between said reservoir and heaterpipe, a reversing-valve constructed and adapted to automatically close the connection leading therefrom to the heater-pipe upon thewithdrawal of water from the system, a feed-pipev v 2. In a water-heater, the combination with.

connected thereto, connections between said reversing-valve and the heater-pipe, and between said reversing-valve and the reservoir, said last-named connection comprising a pipesection, a rod in said pipe-section'and projecting outside the same, said pipe-section and rod being made of metals having different coefficients of expansion, a fuel-supply-valve casing connected to said pipe-section, and a valve in said casing connected to said rod.

thermostatic device located in said last-named connection, and a fuel-supply valve for the 4. As a new article of manufacture, afitting for water-heaters comprising a valve-casing having a chamber provided with three ports, a valve in said chamber controlling one of said ports and adapted to becontrolled in accordance with the flow of fluid through a second port, a fuel-supply valve, a pipe-section connected to the third port, and a thermostatic device in said pipe-section and controlling said fuel-supply valve.

heater controlled by said thermostatic device.

5. Asa new article of manufacture, a fitting for Water-heaters comprising a valve-casing havingachamber provided with three ports, a valve in said chamber controlling one of said ports and adapted to be controlled in accordance with the flow of fluid through a second port, a pipe-section connected to the third port, a rod connected to said pipe-section and extending through and projecting outside the same, said pipe-section and rod being made of metals having different coelficients of expansion, afuel-supply-valve easing connected to said pipe-section, and a valve in said casing connected to said rod, all said parts being combined as a single vendible article.

6. As a new article of manufacture, a fitting for water-heaters comprising a valve-casing having a chamber provided with two circulation-ports and a feed-port, a valve in said chamber-controlling one of the circulationports and adapted to be controlled in accordance with the flow of fluid through the feedport, a pipe-section connected to the other of said circulation-ports and having a reservoir connection, a fuel-supply-valve casing attached to said pipe-section, a valve in said fuel-supply-valve casing, and a thermostatic device in said pipe-section and connected to said fuel-supply valve for controlling the same.

7. Asa new article of manufacture, a fitting for water-heaters comprising a valve-casing having a chamber provided with two circulation-ports and a feed-port, a valve in said chamber controlling one of the circulationports and adapted to be controlled in accordance with the flow of fluid through the feedport, a pipe-section connected to the other of said circulation-ports and having a reservoir connection, a fuel-supply-valve casing attached to said pipe-section and provided with a valve-seat and inlet and outlet ports, a rod secured to said pipe section and extending through and projecting outside ofthe same into the fuel-supply-valve casing, said pipe-section and rod being made of metals having different eoefiicients of expansion, and a valve connected to said rod and cooperating with a valve-seat in said fuel-supply-valve casing.

In testimony whereof I, the said FREDERICK W. RoBER'rsI-mw, have hereunto set my hand.

FREDERICK W. ROllElt'lSllAW.

W itnesses:

ROBERT C. TOTTEN, R0131. D. ToTrEN. 

